Business Insider | 29.04.2017

Migrants, including a pregnant woman, wait for inspection to cross the US-Mexico border, circa 1950s.Getty Images

A central promise of Donald Trump’s presidential campaign was a 55-foot-tall, 2,000-mile-long wall that he pledged to build along the US-Mexico border. Now, 100 days into his presidency, the Trump administration is trying to figure out how to pay for it.

Earlier this week, White House press secretary Sean Spicer said Trump was still determined to make Mexico foot the wall’s estimated $21.6 billion bill, despite the country’s vow that it will never pay for it. Spicer also said American tax dollars may go toward the wall’s construction.

„The wall’s going to get built, folks,“ Trump reiterated on April 25.

The goal of establishing a firm boundary to separate the US from Mexico is nothing new. American presidential administrations have been tightening security along the border for around a century.

Though the divide was formally established in 1824, the US didn’t launch its official Border Patrol until 1924. Inspection and holding stations were created after that, followed by the construction of miles of fences with barbed wire and steel barriers over the next few decades.

Take a look back at the history of the US-Mexico border below. […]